Two weeks before her side hustle's launch party, Olivia Cleary did the math: At five minutes per inch of fabric, she was running out of time to sew 20 polyester scarves.

She started working on the scarves from 7 p.m. until midnight, and 5 a.m. to 8 a.m. — when she had to leave for her full-time architectural design job. She finished the edges of her "crappy little scarves" on a $100 sewing machine that sat atop a folding TV table in the New York apartment she shared with two roommates, she says.

That was in June 2022. Today, her business — called The Clearly Collective — sells silk scarves featuring iconic architectural landmarks. It hit six figures in annual revenue for the first time in October 2023, and its sales have been relatively steady since then, according to documents reviewed by CNBC Make It.

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Cleary left her full-time job in April to spend more time running the business, recently completing a startup incubator program at the University of Virginia, her alma mater, she says.

The Clearly Collective has also created scarves for corporate events hosted by St. Regis Hotels, McLaren Automotive and Bacardi, and will soon add an NFL team to that list, says Cleary. Her scarves featured in donor gift bags put together by the U.S. Olympic Committee for the Paris 2024 Olympic Games.

She credits her ability to whimsically highlight local communities' most iconic landmarks, from the Eiffel Tower to an archway on a college campus. "[My style] is an intersection of architecture, design and marketing," Cleary says, adding: "The designs are a translation of how I understand what a community means to people."

Here's how Cleary built her business while maintaining her full-time job, gaining a boost from TikTok virality along the way.

From outdoor tables to architecture-inspired scarves

Cleary studied architecture at the University of Virginia, graduating in 2020. She moved in with her parents in Boston and, wanting to host friends outside during the Covid-19 pandemic, built two five-foot-long tables out of wooden pallets from a nearby garden store.

When her mom's friends started asking to rent the tables, she made it a side hustle, adding placemats and glassware to her company's rental options. Cleary called her business Backyard Banquet, and took it with her when she landed an architecture job in New York that fall.

Backyard Banquet wasn't easy or lucrative, she says: She had to "schlep" the tables up to her sixth-floor walkup, and didn't have enough time or funds to hire help. But the experience of running a business gave her confidence that she might be able to monetize her creative pursuits one day.

After shuttering Backyard Banquet in 2021, Cleary created a new side hustle to supplement her $45,000-a-year job. She tried painting custom designs onto white jeans, profiting about $20 per pair sold to her friends, but the project proved too time-consuming.

Instead, she looked into printing her designs onto other materials. She settled on polyester scarves as a chic, unique and cost-effective alternative, and sewed the edges herself to add a little polish, she says.

Cleary built a website, and launched The Clearly Collective in June 2022. The business gained traction that fall after she designed an orange scarf featuring UVA's rotunda for a friend and posted it on TikTok, she says.

The post went viral, with at least 40,000 views. Over the ensuing month, her TikTok audience grew, with another video surpassing 200,000 views.

Virality brought orders and pre-orders alike. "Strangers from all over the U.S." requested scarves featuring architecture from colleges like Georgetown University, Duke University and The University of North Carolina at Chapel Hill, Cleary recalls.

Building a side hustle into a luxury fashion business

The pre-orders gave Cleary funds to upgrade her scarves' quality. She tested five new manufacturers before settling on one that offered silk fabric with professionally hand-rolled edges, she says.

Cleary then raised her prices to reflect the luxurious new material, helping her company become profitable in late 2022. The scarves now start at $135 on her company's website, up from an initial price of $45.

In February 2023, a McLaren dealership in San Francisco emailed Cleary, saying they found her on Instagram and wanted her to make scarves for guest gift bags at a car show. It wasn't her first corporate partnership, but felt like an inflection point for the business, she says.

Brand deals now make up about 65% of her company's revenue, Cleary estimates. She declined to share specific revenue figures for her company.

The Clearly Collective's staff is small: Cleary, a contractor and an intern. Cleary says she wants to hire some part-time help, particularly to help with designing, and see how big she can grow the business as her full-time job.

"When I started, I had no idea this was something I could do," Cleary says. "I'm this random girl from Boston. I have no ties to fashion, no ties to luxury. [I didn't realize someone like me] could suddenly establish themselves and say, 'I'm a luxury brand designer.'"

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